Heat exchanger



Sept. 3, 1929. H. BERGQUls-r ETAL.

HEAT EXCHANGER Filed Feb. 16, 1928 2 Sheets-Sheet INVENTORS -m\ Y m. my!

w mw llll IIIIIII sePt- 3, 1929- H. BERGQUIST ET AL.

HEAT EXCHANGER Filed Feb. 16, 1928 2 Sheets-Sheet Patented Sept. 3, 1929.

i-UNITED 'STATES PATENT OFFICE.

HUGO IBERGQUIST, F SWISSVALE, AND PAUL T. KEEBLER, OF J'EANNETTE, PENN- \SYLVANIA, ASSIGNORS T0 ELLIOTT COMPANY, OF PITTSBURGH, PENNSYLVANIA,

A CORIORATION OIE'` PENNSYLVANIA.

HEAT EXCHANGEB.

Application led February 16, 1928. Serial No. 254,692.'

. The present invention `relates broadly to the art of heat exchangers, and more pari ticularly to animproved construction adapted for use in heaters of the indirect type as commonly utilized for the interchange of heat'between a vapor and a liquid. The

utility'of the invention is not limited to anv operation in which the vapor is used entirely as a heating means for the liquid, advantageous results being obtained, incase of a reverse operation in which the primary object of the apparatus is to utilize liquid for condensing the vapor.

For purposes of explanation of the present inventlon, it will be herein described 1n connection with a water heater in which the water passes through the tubes and the vapor passes laround the tubes. In apparatus of this type as ordinarily constructed, it is cus' tomary to provide the necessary reinforcement for the tube sheet by means of one or more staybolts extending` through the `tube y sheet, the-water space vin the water head, and

the water head itself, and efective in tension. Such Vstaybolts have many inherent disadvantages, which it is partly the object 'of the present invention to obviate. In the first place,a staybolt structure requires a` water head of special design in order to afford sufficient strength to satisfactorily carry its own load and the load on the tube sheet. It

also necessitates an o ening through theV water .head for each olt, which openings present a continuing ossibility of leakage.

y Where a pluralityA o4 staybolts is utilized,

each bolt having a shoulder thereon serving as a spacing means between the tube sheet and the water head, it not infrequently happensthat the shoulders willnot be efective i in the proper planes: In such cases the tube .to the square inch, thereby further tending to loosen the joints referred to. In addition to this, the staybolts in projecting through the space in the water head, necessarily occupy part of the room therein and interfere with the desired 'low conditions of the water. y In accordance with the present invention, the use of stayboltsl is entirely eliminated, whereby the water heads may be of any construction desired for the handling of the water regardless of the pressures transmitted to the tube sheets. This is accomplished by the utilization of reinforcing, stiifening or -supporting skeletons cooperating with the tube sheet and holding the same against deformation, suchskeletons preferably being positioned on the tube side of the tube sheet.

In the accompanying drawings there are shown, more or less diagrammatically, for purposes of illustration only, certain preferred embodiments of the present invention,

it being understood that the drawings do not define the limits of our invention, as changes in the design of the apparatus, the construction,l and arrangement thereof, and in the particular construction of the `tube sheets, may be made without departing either from the spirit of our invention o'rthe scope of our broader claims. I

In the *drawings- Figure 1 is a longitudinal sectional view through .one form of heater constructed in accordance with the present invention;

Figure 2 is a View, partly in section and partly in elevation, along the linek II-II of Figure 1 looking in the direction of the arrows and Figure 3 is a perspective view ofa slightly modified form 'of tube sheet. The heater illustratedin Figures 1 and 2 of the drawings comprises a`shell.2 carrying at one end a tube sheet-3 and atthe opposite end a pair of tube sheets 4 and f5. In .this embodlment the tube` sheet 3 constitutes a fixed head, andthe sheets t and 5 floating heads. 5 l jx, f,

The tube sheets are all provided with openings or perforations, as customary in the continnously between the heads. In ther par,- ticular embodiment illustrated,the tubes are arranged in four different nestsfA, B,C and D, providing a four-pass heater, thewater owng in the directies indicated -by the l10o art, for the reception of tubes 7 extending.

for the admission of arrows a. The shell may be provided in own manner with one or more openings 8 steam, and with one or more o enings 8 for the withdrawal therefrom oi) condensate.

The tube sheet 3 cooperates with lan annulus 9 constituting, in effect, a rim for the tube sheet, which may be connected thereto in any desired manner, as by bolting or welding, or it may merely abut thereagainst.

3 in one direction is a rib 10 intersecting a'4 substantially similar rib 11 extending diametrically of the tube sheet in the opposite oppositely extending ample, by means direction. The rib 11 may be provided with anges 12 adapted to be secured to the intermediate portion of-the tube sheet in any desired manner, as, for ex of bolts 14. Intermediate ribs '15 of any desired number and arrangement may be provided.

The rim 9 may be provided in any desired manner with any deslred number of laterall projecting studs 16 adapted to extend through the flange 17 of water head 18 and receive nuts 19 by means of which the water'head is held in position. Preferably the rim 9 will be formed with an inwardly directed shoulder 20 adapted to abut against the tube side of the tube sheet 3 and serve as a positive su port therefor so that upon drawing home t enuts 19 the tube sheet will be rigidly clamped in. position. It stood that the head may be formed with inwardly projectingpartitions 21 dividing it into the desired spaces to obtain themultipass water How. referred to, one of these spaces havin an inlet 22 for the water and another of t e spaces having anv outlet\23 leading therefrom.

In the preferred construction, theribs 10 and 11 are formed int grally of the annulus 9 and the entire assem ly is adapted to receive the tube sheet which is inserted into the recess dened in part by the inwardly directed shoulder 20. In this mamfer the assembly of the parts is facilitated and the desired stren h given' to the tube sheet by the mere act o thus inserting it intothe annulus and against the ribs.

Each of the tube sheets 4 and 5 may likewise be provided with reinforcing ribsi24 extending transversely thereof in one direcskeletons similar tion and with similar intesecting ribs 25 extending transversely thereof' in the \other direction, the ribs 24 and 25 constituting v to that'formed by the annulus 9 andthe ribs 10, 11 and 15. u Also cooperating with .each of the tube sheets 4 and 5 is a. ead 26,\preferably bolted thereto in, afrnanner similar to that described desired, the remforcingfribs 24 and 25 may cooperate with a tlplieripherally extending reinforcing 27, e presence or absence of such a rib ,heads Extending diametrically of the tube sheet baffles 30 and Avheld in y supporting tube sheets will be under- .F

ing ribs 10 and 11.

depending upon the construction of the heater.A g

Suitable pads 28 constituting a sliding support for the ioating heads within the shell 2'may be provided, as is customary 1n the art, and a shell may carry a closure head 29 permitting accessl to and inspection of the floating heads. f

Ifsdesired, the vapor space between the may be provided with anv form of position by suitable supports 31.

In operation, upon the admission of water .to the interior of the water` heads, the tube sheets are'subjected to a considerable pressure tending to deform the tube sheets. This tendency toward deformation is effectively prevented, however, by the skeleton-like supports comprising beam-like means extending transversely of the tube sheets and upstanding from-the general plane of the tubesheet body. This results in the provision of selfpossessingl the advantages referred to.

In Figure 3 of the drawings there is indicated,'in perspective, a slightly modified form of' tube sheet designed for 'use with either a single pass or a fourpass heater, depending upon the construction of Nthe water boxes. The tube sheet is formed with openings 6 for the reception tof the tubes and'is shown cooperating with a skeleton-like frame comprising .an annulus 9 and intersect- The ribs are shown (as beingl bolted directly tothe tube sheets, similar to thefconstruction indicated in Figure 1 for the floating heads 4 and 5, and the tube sheet is illustrated as having studs 16' projecting therefrom for cooperation with a waterhead. The annulus 9 may be provided with any desired number openings 33 for Athe .reception of bolts, by means of which `Vit may to the periphery of the tube sheet. This lfigure illustrates a form of tube sheet adapted toconstitute the floating head of a heater, as will be apparent to those skilled in the art. 4

Certain-advantagesof the present inven tion arise from the construction of what may be callede a stayless heater providing unobstaructed water spaces` and self-supporting tube sheets. -Such a construction obviates the possibility of deformation ofthe tube sheets either during the original installa-I tion or during use, and obviates the necessity of providing the suc ashave heretofore been necessary for the reception of the stays.

`We claim: l' n 1. In a heat exchanger, a. supporting skelebe bolted directly water heads with openings ton, and a tube sheet lying against and sup- 105 of bosses 32 and a tube sheet lying against and supported by ing skeleton for tube' sheets comprising a rim said skeleton. and a rib secured thereto, said rim being 3. In a heat exchanger, a supporting skeleshaped for the insertion of a tube sheet. 10 ton comprising a rim and a transversely ex- In testimony whereof we have hereunto set tending beam-like rib, and a tube sheet lying our hands. A y against and supported by said skeleton. f HUGO BERGQUIST. 4. As an article of manufacture, a support- PAUL T. KEEBLER. 

